Anode and method of making the same



Jan. 31, 1928.

' 1,557,553 P. SCHWARZKOPF ANODE AND METHOD OF MAKING THE SAME Filed June 15, 1922 Patented Jan. 31, 1928.

UNITED STATES PATENT. OFFICE.

PAUL sonwaazxornor crrannozrrnneune. GERMANY, assrsnon ononn-r-rannro nnrrrscnn eLnnrAnENnABRIK, .mcnannxunrz & ion. ING. rnnnsenwana HOPE-G. ivrn. H., or BERLIN, GERMANY.

ANODE AND IvIETHQD ,MAKING THE Application filed June 15, 1922; Serial No. 568 521, and in Germany June 21, 1921.

My invention relates to an anode for Rout-gen apparatus and a process of making the same. The invention consists in the structure of the anode and the method of producing it, which will appear in detail as the description proceeds.

In the accompanying drawings, Figure 1 shows an anode such as has been hitherto used; Figures 2 and 3 are sections on the lines A and CD, respectively, on 1; Figs. sand 5 are face and side views, respectively, of one form of my improved anode; Fig. 6 shows a side view of a moditied form of the same; Fig. 7 is a diagrammatic View indicating the operationbt the anode shown in'Fig. 1; Figs. 8 and Stare face and side views, respectively, indicating,

the arrangement of the fibers-o-l themetal' in my improved anode; Fig. 9 is a side View ott'a further modified form ot'my improved anode.

Anodes tor Rontgen tubes have been made of tungsten and similar metals. In working tungsten, molybdenum, and similar diilicultly fusible metals, bars are first formed by sintering compressed powdered material. These bars are usually sintered by passing an electric current through them, preferably while surrounded by neutral gases. It is difficultto form bars of any considerable size in this manner. A bar having; a thickness of 1.5 or n'iillin'ieters and a length of 15 or 20 centimeters requires a current of thousands of tlll'lPOl'QS. For this reason the size oii such bars is very limited. The material is so refractory that bars of even this size cannot be formed practicahly by fusion. and casting.

liars formed in this manner have been rolled lengthwise to form strips or plates for various purposes. These strips or plates have notbeen more than millimeters in width, as the longitudinal rolling oft the bars does not. greatly increase their width. Furthermore, when such bars are rolled the edges of the strip do not have the same structure as the cei'itral portion of the strip, but are likely to be cracked and in.- :lerior.

In making such an anode as shown in F is. l, a sintered bar has one end drawn out, as shown at s in Fig. 1, while the other end 70 ren'iains in substantially the original condition. If it is worked at all it will be stretched lengthwise, but anysuch working must be slight in order to retain the desired extent of surface on the receiving end 7. i

In forming my improved anode, a sintered bar may be used having a less diameter than the bar used to form the anode shown in Fig. 1. Theentire bar is preferably lengtlr ened by mecahnical treatment, asby ha1nmering or rolling to lengthen it to some-em tent. This preliminary lengthening is not absolutely necessary, but is preferable in order to compact the material and give it the desired strength for subsequent treatment; i

After the lengtheing, the end whiclris to form the anode is broadened by mechanical treatment, asby hammering orroll'ingg, until it attainsthe desired form. The anode may beused in the shape shownin Figs. l; and 5 or may be given a V-shape, such as shown in Fig. 6. This V-shape is preferred. The plate may be bent from the shape shown at g in Fi 5 to the shape shown at h in Fig. 6 while the metal is hot, or it may be formed directly in the shape shown in F ig. 6 by rolling it with suitably shaped rollers. If desired, the plate may be made long enough so that it can be bent as shown in Fig. 9. the side 2' presenting the receiving surface, while the bent front end j will constitute a cooling rib; in any case where the V-shape is given the plate, any portion of the plate which is at an angle to the receiving; surface will act as a cooling rib. The portion j of the plate may be bent at right angles, as shown in. full lines in Fig. 9, or it may be bent up to the position shown in dotted lines in that figure.

The advantages of my improved anode and the manner of making it may be briefly stated as follows:

In the first place a bar of less diameter it has such treatment as will tend to create fibers running longitudinally of the anode, as shown at a. In my improved anode, the receiving surface has been given mechanical treatment both lengthwise and transversely, so that the material is comparatively dense. Furthermore, the transverse Working takes place after the longitudinal working and is considerably more extensive, so that the fibers extend transversely, as indicated at a in Figs. 8 and 8. In all instances the fibers in the portion 8 will run longitudinally of the holder. This is desirable in the holder, but in the receiving surface of the anode itself, it is undesirable. lVhen the rays or electrons strike the anode in the direction indicated by p in Figs. 7, 8 and 8?, there While I have disclosed a specific e1nbodi ment of my invention, it Will be obvious that various departures from the disclosure may be made Within the scope of the appended claims without departing from the spirit of my invention.

What I claim is:

1. An anode for a Rontgen tube C(Jll'llll'lfi ing a receiving surface of fibrous metal haw ing its fibers transverse the direction of the current.

2. An anode for a Ilontgen tube comprising a receiving plate of fibrous metal having its fibers transverse the direction 01 the current and having an integral supporting bar.

3. An anode for a Rontgen tube comprisinga receiving plate o'l fibrous inetal haw ing its libers transverse the direction of the cin'rent and having an integral supporting bar of fibrous metal, the lihers in the said her running parallel with the current.

4:. In a liontgen ray device, a plate-sln1ped anode, the crystals of which extend in a plane enclosing an angle with the directirm oi travel of electrons.

5. In a lliintgen my device, an anode in the form of a that plate having a red at one end, the crystals of said plate extending in the plane thereof, and the cross section ol' said plate being at an angle to the cross section of the rod. 

